Thread controller for sewing machines



Aug. 6, 1929. J. R. MOFFATT THREAD CONTROLLER FOR SEWING MACHINES '3 Sheets-Sheet 1.

Filed Aug. 23, 1926 Aug. 6, 1929. J. R. MOFFATT THREAD CONTROLLER FOR SEWING MACHINES Filed Aug. 23, 1926 5 Sheets-Sheet 2 Aug. 6, 1929. J. R. MOFFATT THREAD CONTROLLER FOR SEWING MACHIQES Filed Aug. 25, 1926 3 Sheets-Sheet 3 Patented Aug. 6, 1929.

UNITED STATES PATENT OFFICE.

JAMES R. MOFFATT, OF CHICAGO, ILLINOIS, ASSIGNOR TO UNION SPECIAL MACHINE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

THREAD CONTROLLER FOR SEWING MACHINES.

Application filed August 23, 1926. semi No. 130,954.

The invention relates to new and useful improvements in thread controllers for sewing machines, and more particularly to a rotary thread controller which is especially 5 adapted for use in connection with the looper thread of a locked chain stitch sewing inachi-ne.

An object of the invention is to provide a thread. controller for sewing machines including an annular member of uniform diameter and having a. cain-sl'iaped peripheral edge and cooperating thread guides, one lo- :ated within and one without said peripheral edge. which can be mounted. on a shaft intermediate the ends thereof without any liabil ity of the thread controlled thereby being wound on to the shaft. p

A -lurther object of tlie invention is to provide a thread controller of the above type wherein said guides are so mounted that they can be readily moved to amore accessible point for threading. I

A further object of the invention is to provide a controller of'the above type wherein the thread controlled is positively carried forward in a circumferential direction by a controlling cam.

A further object ot the invention is to provide a thread controller of the above type wherein thethread controlled thereby is re leased at titties, and after it isreleasedya frictional drag is placed thereon to prevent the thread "from being given up too rapidly. A. still further object o'l theinvention is to having a thread retaining linger which is znljnstahlein an axial direct-ion relative to the rotatable controller and also circumterentiallv ot the thread controller.

obvious and will in part be hereinafter more fully disclosed. 3

in the drawings which show by way of provide a thread controller of the above type These and other objects will in part be element is t agair st rotation, and thissleeve extends into thread controlling mechanism in top plan "VIEW;

Fig. 3 is an enlarged sectional view showing the thread controller with the rotating threznil for the needles to enter;

I Fig. 7 is a view similar to Fig. 6, but showing the thread controller as operating to take up or hold the looper threadduring the forward movement of the looper;

Fig. 8 is a view similar to Fig. 7 but showing the looper thread as retained by the fric-.

vtional drag thereon, and given to the loopers during their forward movement into the needle thread loops;

Fig. 9 is a sectional view on Fig. 8; I

Fig. 10 is a perspective view of a supthe line 9, 9 of porting sleeve carrying the cast-ofi' and re tainer, and

Fig. 11 is a perspective view of the rod in which lhethread guides are formed.

The invention. is directed broadly to a thread controller for sewing machines, and

more particularly to a thread controller which especially adapted for controlling the looper thread in a locked chain stitch machine. This thread controller is of the type shown in my prior patent application Serial. No. 715 421; filed May 23, 1924. and the broad invention is claimed therein. The thread controller includes a rotating annular member of uniform diameter and having a cam-shaped peripheral ec Pretei,ably.tliei'e are two annular cams, one within the other. The rotatable controlling element in the present embodiment of the invention mounted on a rotating sh a it intermediate the ends thereof. On the shaft on which the controlling mounted is a sleeve which is fixed the eylimlr'ieal or annular r tating member 21 c1 crnnterential direction by the rotation of the controlling element. During the forward movement of the thread it is also moved axially ot the controlling element a point v-rhere it is cast oil from the take-up cam of the coitrolling element. There are'thread guides located, one i ithorit the periphery and the othe in the periphery of the rotating cont element, as in my prior application. taining finger is adjustably mount d stationary sleeve. is so positioned relatively to this finger that when the thread cast off i the take-up cam, a fri drag will be placed thereon so that tl e thread will not be given up too rapidly. The retainin fi r is capable of adjustment for varying the trictional drag, and so as to accornnndate threads or? different sizes. The controlling element 1 in the is also provided With a notch in its peripheral edge so as to Jrovide :tor a seeond taking up of the thread during the rotation of the controlling element.

Referring more in detail to the c I have shown my thread controlling mechanism as used in connection will t trolling of thelooper thread in a e machine. The sewing machine consists bed plate 1 having an overhanging arii L carrying a needle head 3 in which reciprocatcs a needle l carrying needles 5 an These needle" are set in a line inclines co he line of feed, and there is a threaded loci I cooperating with each needle.

L 7 cooperates with th needle 5, and the lot e1 8 cooperates with he needle 6. T l carrying loopers are mount d on carri r 9 pivoted at 10 to a loop 11. The looper carrier OSCllllt. support by a link 12, and the loo is oscillated by an arm cooperat 2 g eccentric on the main shaft 1%. T

all of the usrial construction. con"rolling mechanism consists o1 cylindrical or ann lar member '15. trolling nember 15 consists of a hub 2 3.6 on which is termed an i: tegrral di. l t the outer edge of the dis 7 is :1 cyl cal o flange portion 18, and spacerl from this outer flange portion 18 is a sinilar flange portion 19. The flange portion 1 is of uniform diameter throughoutthe entire cir mnt'erence of the controlli member, and likewise the flange member is of uniform dieinti roag cireunterence, although th di meter, or course, of the flange member 18 it greater tl i the diam ter of the flange member 19. This nrovides a Lular space 20 in \v'lllCrl is located the "e t-o "icinber and a portion of the retaining The cor trolling inen ber 15 1 d on main shalt ii and is secnred o by a screw 21 w neh is located in b 145. Mounted on the ll'lilll shaft 1 le 22. This sleeve 22 is pr vided will a re t the right-hand end thereof as sho n in Jig. 5 nl es the hub of the controll'ng so member lo. The hub is ntirely housed within n cs, ans the s t screw 21 is coniple red by the sleeve The sleeve in y loose fit with the snail 1% and is helt ctr lo I 2 pi to th late 1 1 in l" e 22.

n D 6 in Fig. l of the drawn .nwe d sions guide same w; on

pass uneeriiezzt ppe thence he threu eye 2 i eof theannulz: i e element.

mg n e 35. the th the .enient n neriphe thread controlling element at all points in the eireuinterence thereof, except the main cut away portion which forms the main take up cam 38. This cut away portion is of su'liicient size as to permit the ra-ising of the inner guide. I The arn1l37 has a right-angled portion 39 which. is mounted in a recess 40 in a bracket 41 secured to t 1e bed plate 1 01"" the machine. This angular portioi '39 is provided with an ojllset42. A spring 23 ca 'ried by the bracket {ll bears against this o-illsct and will retain the arm either in horizontal possition or in raised position. When i its horizontal position, the arm rests on an adjustable screw 44, and this determines the vesition of the arm relative to the rotatable thread controlling element. hen the machine is threaded, the arm is raised so that the thread eyes are accessible for threading and the arm an be readily l'lllt-Ztll by turning the main shaft so as to bring the cut away space directly above the inner end of the arm 37 in which the. thread eyes are former The cylindrical portions of the thread controlling element are not only cut away to form the take-up can) 38, but are also cut away to form a. take-up shoulder 45. The inner edge of the retaining; linger 28 is with in the peripheral edges o l? the. cylindrical p tions, but said retaining finger is of sach thickness and so positioned that the threr,

can slide along; between the retainer and edge of the'cylindrical portion and can b alien up for use Without the rapid giving u of the thread. The talte-up'cani 38 is r01 by the inclined edge of the cylindrical incinhers, and these inclined edgesterinina-te in,

more or less of a sharp shoulderSS. T he in clined face oi? the cast-oil member 27 terminates in a notch 27 which is disposed at the outer sideol theextreine lateral edge of the cylinth'ical members of the roh tinacontrolling; member.

The construction of the rotating controlling;- element and the parts associated therewith will pr ybably be host understood by a description of the method ot operatmn. T he tal e-up cam 88 coinesinto management with the looper threads between the thread eyes an d 236 when the looper is on lite retracting inown'iont. it is atthis time that the loeper thread should be drawn tautin order that the tln'aid running; from the cyeoit the loopor LO the Pl'OVHHlH stitch, Will he held sahstantially taut and insure the needle ente any; rtspropcr thread triangle formed by the looger thread just referred to, the body of the loo/per and the needle thread loop which is, at this time on the looper. The take-up cam 38 engaging the looper threads carries them agai 1st the inclined face of the cast-oil ll'lClillKl 27, the hrcads will ride along this inclined edge and also along; the inclii. edge of the take-hp 321121 38 until. the thrcaos reach the shoulder 88*, and they will be carried by the shoulder 38 to a point where they are cast oll into he notch 27. at will be noted that in i 27 is a a considerable distance Cll'CllllllQl'dlltially of the rotating controlling element from the thread eyes and 'lherelfore, the thread as it is carried forward and cast oil into this notch, will be carrital n. inly in a cireuinilerential (lli'QCtit n of the thrmid controlling element. It will he carried to a certain extent an! y of the thrc; d con rollirg; element so that it can be cast :hniterential inovenmnt oi the t. tive to the thread controlling i; enah a considerable quantity of thread to ln fi'zllien up witlmut laying an excessive o .'erlurn;; oi? the cylindrical portions oi the controlling element.

After the loopers leave the needle thread loops, the lil'iread is held under gentle trictional d as; control upon the moving straight edges of the controlling element and tire retaining' lingers 28. Just as the looper stops on its rearwaid. movement, the Shoulder formed by cutting a\ my the peripheral edge l relaot the shell. members of the rotating; controlthrough thelooper or held from inoi'eanent' forward in trout of the looper so that the looper will slide alone; the looper thread unti I the looper oint reaches and e: tors the needle i thread loop. This prevents elacl (lUL'Gizll from forming in front, of the pointo'f the loope which might force the needle threal loop to one veide and cause a shipping or st'te Aft-er the leo'nei' point is well, into tl eedle' ie n thread loop, then the shoulder 45 UOIIUEHZ on- M will'release tlu loo er posiie the notch thread heldby the frictional drag; of the retaining linger on the looper thread. The looper movingvn to the forward end (it its stroke requires thread to form its thread this; is given up to the iooper by the loeper thread slidin alone the straight peripheral 32'; edge of: the rotating ooutrolln E -L'IEVI. V, hut

suhj ect to the frictional drag what it i. not given up too rapidly. O'i' course, wl on the space in the cut zway shell reaches the retaining linger then the thread )e entirely released auu may be drawn i i a position sulfltantially straight from the eye 35 to the thread eye 3".

By loosening the clamping 9 ing the bracket 2h the thread 1* am he shi t'ted so at; to vary the ran;

the loopr thread, or so as to accon exudate (lliliQlTSl'llln zed threads. can also he adjusted circninterentially of the operating shaftby loosening the clamping rl; rea d not I support sleeve. This adjn tn'ient permits the hanging of the time 01" the casting oil oil the thread to enit different conditions in the machine. in

,tch

and the looper thread will he merely loo gm, and

'lhe cast oli inen'iher n asmuch as the sleeve 22 is stationary, there is no possible chance of the ooper thread l ing wound up on to the she t l or the inner parts of the rotating thread controlling element. Y

While 1 have described the rotating thread controlling element as inou ed on the shaft adjacent the bed plate of the machine, it will be understood, of course, that this thread controlling element may be mounted on a top shaft in other types of machines. It must be mounted, of course, on rotating t, but this rotating shaft may be select 1, or positioned at any desired point in the machine.

While l have described the thread controlling mechanism as particularly adapted for controlling the looper thread of a locked chain stitch. machine, will be understood that it may also be used for other types of machines. and for controlling the needle thread, as I believe I am the first to develop a thread controlling mechanism wherein the thread is controlled by a rotating annular cam, with guides for the thread positioned rithin and \ithout the peripheral portions of the controlling cam where said thread controlling cam is mounted on a shaft intermediate the ends thereof.

' It is obvious that minor changes in t tails of construction and the arrangemen= the parts may be made without dep: from the spirit of the invention as set for i in the appended claims.

Having thus described the invention, what I claim as new and desire to secure by Lettors-Patent, is

1. The combination of ashaft, thread controlling member mounted on said shaft and having a laterally projecting thread engaging surface overhanging said shaft, thread guides located one within and one w thout the periphery of said thread engaging surface for guiding the thread for engagement therewith, said thread engaging surface being in part can'i-shaped andin part straight relative to its path of travel, a stationar cast-off finger adapted to be engaged by tl e thread on the cam-shaped surface for forcing the same laterally off from said sur face. and a retainer finger parallel with the "1 ht edge of the controlling member for placing a frictional drag on the thread as it passes along said straight edge.

2. The combination of a shaft, a disc fired to said shaftand having a laterally projecting cylindrical do go, said fi ge being cut away in part at its outer edge to form a thread controlling cam, thread guides, one within and one withoutvsa d flange, a staion a rv member extending beneath said flange to a point ad acent the disc, and a sta 3. The combination of a shaft, a disc fixed to said shaft and having alaterally projecting cylindrical flange, said flange being cut away in part at its outer edge to form a thread controlling cam, thread guides, one within and one without said flange, a stationary member extending beneath said flange to a point adjacent the disc, cast-oft member associated with said llange for moving the thread ofi from said cam, and a retaining finger for putting a frictional drag on the thread when released from the cam,

said cast-off member and said retaining finger being mounted on said stationary member.

-l, The combination of a shaft, a disc fixed to said shaft and having a laterally projecting cylindrical flange, said flange being cut away in part at its outer edge to form a thread controlling cam, thread guides, one within and one without said flange, a stationary member extending beneath said flange to a point adjacent the disc, and a cast-off member mounted on said stationary member and associated with said flange for moving the thread off from said cam, said flange hav n a second cut-away portion for and talting up the thread a second during the rotation of the shaft. 5. The combination of a shaft, a disc fixed to said shaft and having a laterally projecting cylindrical flange, said flange being cut away in part at its outer edge to form a thread take-up cam, thread guides, one within and one without said flange, and a stationcast-off member and a stationary retainiinger associated with said flange, said finger being located along the outer edge of the flange and spaced therefrom so as to put a frictional drag on the thread when released from said cam.

6. The combination of a shaft, a disc fixed to said shaft and having a laterally project-- ing cylindrical flange, said flange being cut away in part at its outer edge to form a thread take-up cam, thread guides, one within and one without said flange, a stationary cast off member, a stationary retaining finger associated with said flange, said finger being located along the outer edge of the flange and spaced theref om so as to put a frictional drag on the thread when released from said cam, and means for adjusting the linger toward or away from said flange.

7. The combination of a shaft, a disc lixed to said shaft and having a laterally projecting cylindrical flange, said flange being cut away in part at its outer edge to form a thread take-up cam, thread guides, one within and one without said flange, a stationary cast-off member and a stationary retaining lin er associated with said fian said linger being located along the outer edge of the and spaced therefrom as to put a frictional on the threes when released from said irag lion of a sh,

to said shaft and hav' pa 1 spaced laterally PIOJCClLlQg flan said flanges being cut away in part at their outer edges to form annular thread take-up canis, thread guides, one within and one without said flanges and disposed so as to hoh the thread for engagement with said cams, a s'l'a 'ionary cast-off member extending into the space between said flanges, a slationary re" iniin}; linger on tending into the space between said flanges I and having its edgg'e adjacent the flanges subedges of the flanges so that a frictional drag);

is placed on the thread afterit released from the take-up can 9. The combination of I t said shaft and having pa 1 erally projecting flanges, said flanges being cut away in part at their outer or to form annular thread take-up cams, thread guides, one within and one without said flanges and disposed so as to hold the thread for engagement with said cams, a stationary cast-off member extending into the space Jill-W083 said flanges, a stationary retaining; finger ext nding into the space between said flanges and having" its edge adjacent the flanges substantially parallel to and spaced from the edges of the flanges so that a frictional drag is placed on the thread after it released from the take-up cams, said disc being so disposed on the shaft that the flanges overhang the shaft, and a stationary member extending; beneath the flanges to a point adjacent said disc and all. the way aroinid. said shaft as lo prevent the thread from catching and winding on said shaft.

10. The c-(mibination of a shaft, a disc, a hub carrying said disc and secured on said shaft, said disc haying a laterally projecting cylindrical flange cut away at its outer edge to form a thread controlling cain surface, thread guides, one within and one without said flange, a stationary cz st-oflj' member a,- sociated with. said flange, said disc being so disposed on said shaft that the flange overhangs the shaft, and a sleeve loosely mounted on said shaft and extending beneath said flange, and means to hold said sleeve stationary.

11. The combination of a shaft, a disc, a hub carrying said disc and secured on said shaft, said disc having a laterally projecting cylindrical flange cut away at its outer edge to form a thread controlling cam surface, liln'ead guides, one within and one without said flan e, a stationary cast-off member associated with said flange, said (use being so a disc fixed el spaced latdisposed on said shaft that the flange overhangs the shaft, a sleeve loosely mounted on said shaft and extending beneath said flange,

and means to'hold said sleeve stationary, said sleeve having a recess formed its inner end adapted to extend over and house said hub.

The combination of a shaft, a disc, a hub carrying said disc and secured on said shaft, said disc having a laterally projecting cylindrical flange cut away at its outer edge to form a thread controlling cam surface, thread guides onewithin and one'without said fian e, a stationary cast-oil member associated withsaid flange, said disc being so disposed on said shaft that the flange overhangs the shaft, a sleeve loosely mounted on said shaft an d extending: beneath said flange,

means to hold said. sleeve stationary, said sleeve having a recess formed in its inner end adapted to extend over and house said hub, and a retaining: finger mounted on said sleeve and amending along the outer edge of said flange for placing a frictional drag on the thread when released from said cam.

13. The combination of a shaft, a disc, a hub carrying said disc and secured on said shaft, said disc having a laterally projecting cylindrical flange cut away at its outer edge to form a thread controlling cain surface, thread guides, one within and one without said flz'mgre, a stationary casted n'ieinber as sociated with said flange, said disc'being so disposed on said shaft that the flange over hangs the shaft, a sleeve loosely mounted on said shaft and extending beneath said flange, means to hold said sleeve stationary, said sleeve having a recess formed in its inner end adapted to extend over and house said hub, retaining finger mounted on said sleeve and extending along the outer edge of said flange for placing a frictional drag on the thread when. released from said cam, and means whereby said finger can be shifted endwise of said sleeve.

14. The combination of a shaft, a disc se cured to said shaft and having cylindrical flanges projecting laterally therefrom, said flanges being cut away in part to form thread controlling surfaces, thread guides located one within and one without said flanges, an arm carrying: said guides, and means for supporting; said a rim whereby when said cut away portions of the flanges are over said inner guide, saidiu'in can be raised and the guides positioned for threading. I

15. The combination of a shaft, a disc fixed to said shaft and having; a laterally projecting cylindrical flange, said flange being cut away in part at its outer edge to form a thre d fake-up can), thread on ides, one within and one without said flair? v, a stationary castoff member, and means for adjusting: said casto'll' lneniber circuinferenfially of said shaft.

16. The combination of a shaft, a

thread controlling member mounted on said shaft intermediate the ends thereof and having a laterally projecting thread engaging surface, thread guides located one betwen the periphery of said thread engaging surface and the shaft and the other outside of said peripher for guiding the thread for engagement with said thread engaging surface.

17. The combination of a shaft, a thread controlling member mounted on said shaft intermediate the ends thereof and having a laterally projecting thread engaging surface, thread guides located one between the periphery of said thread engaging surface and the shaft and the other outside of said periphery for guiding the thread for engagement with said thread engaging surface, and a stationary sleeve encircling said shaft and extending beneath the thread engaging surface so as to prevent a loose end of thread from catching and winding on said shaft.

18. The combination of a shaft, a thread controlling member mounted on said shaft intermediate the ends thereof and having a laterally projecting thread engaging surface, thread guides located one between the periphery of said thread engaging surface and the shaft and the other outside of said periphery for guiding the thread for engage ment with said thread engaging surface, a stationary sleeve encircling said shaft and extending beneath the thread engaging surface so as to prevent a loose end of thread from catching and winning on said shaft, and a castoft' member and a retaining finger mounted on said stationary sleeve and cooperating with said thread engaging surface for casting the thread off from said surface and for retaining the thread after it is cast off.

19. The combination of a shaft, a disc secured to said shaft and having a cylindrical flange projecting laterally therefrom, said flange being cut away in part to form a thread engaging surface, thread guides located one within and one without said flange, an arm carrying the inner thread guide, and means for supporting said whereby when said cut away portion of the flange is over said inner guide, said arm can be raised and the guide positioned for threading.

In testimony whereof, I affix my signature.

JAMES R. MOFFATT.

n a D 

